Spessartine's name is a derivative of Spessart in Bavaria, Germany, the type locality of the mineral.[3][4] It occurs most often in granitepegmatite[3][4][5] and allied rock types and in certain low-grade metamorphicphyllites. Sources include Australia, Myanmar, India, Afghanistan, Israel, Madagascar, Namibia, Nigeria, Mozambique, Tanzania and the United States.[2] Spessartine of an orange-yellow has been called Mandarin garnet and is found in Madagascar. Violet-red spessartines are found in rhyolites in Colorado and Maine. In Madagascar, spessartines are exploited either in their bedrock or in alluvium. The orange garnets result from sodium-rich pegmatites. Spessartines are found in bedrock in the highlands in the Sahatany valley. Those in alluvium are generally found in southern Madagascar or in the Maevatanana region.[7][8][9][10][11]
Spessartine forms a solid solution series with the garnet species almandine.[4][5] Well-formed crystals from this series, varying in color from very dark-red to bright yellow-orange, were found in Latinka, Rhodope Mountains, Kardzhali Province, Bulgaria.[12] Spessartine, like the other garnets, always occurs as a blend with other species. Gems with high spessartine content tend toward a light orange hue, while almandine prevalence induces red or brownish hues.[13]